In the world of architecture and interior design, the choice of materials plays a crucial role in defining the aesthetic appeal, functionality, and longevity of a building. As many perhaps already know, stainless steel doors and frames are synonymous with durability and modern design. In this comprehensive guide, we take a brief look into the realm of stainless steel openings, exploring their properties, diverse applications across industries, various types and finishes, and the manufacturing processes.

What is Stainless Steel?

Stainless steel is a corrosion-resistant iron-based alloy composed of iron, chromium, nickel, and other elements, depending on the specific grade. Its unique composition gives stainless steel its remarkable properties, including resistance to rust, staining, corrosion, and bacterial growth, making it an ideal material for a wide range of applications. It achieves high levels of corrosion resistance due to a relatively small content of carbon (usually 0.08–0.25%), a high content of chromium (12–26%), and sometimes Nickel (up to 22%). The addition of chromium forms a protective oxide layer on the surface of the steel, known as the passive layer, which further enhances its resistance to environmental factors. Whether subjected to harsh weather conditions, high traffic areas, or frequent use, stainless steel doors and frames maintain their structural integrity, requiring minimal maintenance while offering lasting performance.

Use Cases

Because of the properties mentioned previously, stainless steel doors and frames are commonly used across a wide range of industries. Some of the most common industries include: commercial, healthcare, food processing, industrial, and detention:

Commercial:

Stainless steel openings are a popular choice in commercial and sometimes residential construction projects. This includes office buildings, schools, condominiums, and luxury homes. Their sleek appearance, durability, and low maintenance requirements make them an attractive option for both interior and exterior use in commercial applications.

Healthcare Facilities:

The term healthcare facilities can cover a wide range of institutions that all have one thing in common; a need for cleanliness. Places like hospitals, clinics, laboratories, and pharmaceutical plants often rely on stainless steel doors and frames due to their hygienic properties and resistance to bacterial growth. These facilities often require doors that can withstand frequent cleaning and sterilization, making stainless steel an ideal choice. Stainless steel openings have hard, smooth, and non-absorbent surfaces which are easy to clean, making it difficult for bacteria to adhere and grow. Not to mention that because of their cleanability, corrosion resistance and non-aging properties, they can last for decades all while adding a unique aesthetic appeal to the space.

Food Processing:

Similarly to healthcare facilities, places such as commercial kitchens, restaurants, food processing plants, and food packaging plants are all environments where cleanliness and sanitation are a top priority. Stainless steel doors and frames are favoured for their durability, ease of cleaning and resistance to corrosion from food acids and cleaning chemicals.

Industrial Settings:

Manufacturing plants, power plants, warehouses, and all sorts of industrial facilities use stainless steel openings to benefit from their durability and strength, which can withstand heavy use, harsh environmental conditions, and exposure to corrosive chemicals.

Detention facilities:

Detention facilities can include jails, prisons, courthouses, and treatment centres. All of these buildings are designed with security as a top priority. Stainless steel doors and frames are an excellent option when it comes to secure and robust openings, especially when thicker gauges are used. Often, the combination of security, corrosion resistance, and cleanliness that stainless steel offers makes it the best option for many areas within a detention facility.

Types

Stainless steel doors and frames are available in various types and finishes to suit different design preferences and requirements. In the case of the construction industry, 304 stainless steel and 316 stainless steel are by far the most commonly used.

304 stainless steel is composed of 18% chromium and 8% nickel, with small amounts of manganese, silicon, phosphorus, sulphur, and nitrogen. It is known for its excellent corrosion resistance in a wide range of environments. It is suitable for applications where exposure to moisture and some chemicals is expected. However, it is somewhat susceptible to chloride corrosion in coastal and industrial environments.

316 stainless steel has a similar chromium content (16-18%) as 304 stainless steel, 316 stainless steel contains 10-14% nickel and 2-3% molybdenum. This addition of molybdenum enhances its corrosion resistance, especially in chloride-rich environments such as places exposed to ocean water and chemical processing plants.

In summary, 304 stainless steel is suitable for general-purpose applications, while 316 stainless steel is preferred for harsher environments where superior corrosion resistance is crucial. Understanding the differences between these grades helps in making informed decisions regarding material selection for various industrial and commercial applications.

Finishes

In addition to the different types of stainless steel and their specific compositions, both 304 and 316 stainless steel can be treated with various finishes to enhance their aesthetic appeal and improve their performance in specific applications. Some popular finishes include:

#2B Finish, also known as a 2B mill finish or cold-rolled finish, which is achieved by cold rolling the stainless steel sheet or coil and then annealing it in a controlled atmosphere. It results in a smooth, reflective surface with a uniform grain pattern.

#3 Finish, also known as a ground finish or coarse-grained finish, is achieved by grinding the surface of the stainless steel with abrasive belts or wheels. This process leaves a rough, non-reflective surface with visible grinding lines.

#4 Finish, also known as a brushed finish, the #4 finish is achieved by brushing the stainless steel surface with abrasive materials in a unidirectional pattern. This process creates a distinctive, matte appearance with a fine, consistent grain structure.

#8 Mirror finish is a highly polished finish, also known as a mirror finish. This is achieved by mechanically polishing the stainless steel surface to a mirror-like appearance. It involves multiple stages of polishing with progressively finer abrasives until a high gloss is achieved.

Finishes

Manufacturing with Stainless Steel

The manufacturing process of stainless steel doors and frames is much the same as with regular steel. It begins by cutting the steel sheets to the desired dimensions, often using a laser cutter. Once cut, the sheets are bent into various components, including door skins, frame jambs, hardware reinforcements, and other parts using a press break. Welders then begin to TIG or MIG weld the components together. The assembly process follows where hinge, lock/strike, and other hardware preparations are fitted to the doors and frames. The last step differs from regular steel as the stainless steel must undergo surface treatments, which may include any of the finishes previously described.

One crucial aspect that sets the manufacturing of stainless steel doors and frames apart is the strict requirement for precision and accuracy during the cutting, bending, welding and assembly stages. Unlike some other materials used in the door and frame industry, such as wood or aluminum, stainless steel does not allow for the use of body fill to mask imperfections or errors during the fabrication process. This means that every step of the manufacturing process must be executed with meticulous attention to detail, as any imperfections will be noticeable on the finished product.

Conclusion

Stainless steel is a fantastic option to have for doors and frames. They offer a unique combination of durability and aesthetics that other materials simply can not compete with. Not to mention the variety of types and finishes that give the designer or architect the ability to customize them to their specifications. Although the manufacturing process can be rigorous, the end result is worth the trouble.